The field of the invention is geometrical instruments having pivoted contacts and the present invention is particularly concerned with a mechanical sensor moving relative to the instrumentation and consisting of one part which is fixed to the housing and of another part which is movable but connected to the first part by an articulating multi ball and socket member.
At least one test-value transmitter detects the relative motion between the test sample and the sensor. A counter follows the sensor and a signal is generated in the apparatus at the instant of impact between the sensor and the test sample, this signal then being stored in a memory. The memory stores the test value present at the test-value transmitter at the instant of impact.
The state of the art of contact sensors may be ascertained by reference to U.S. Pat. Nos. 3,905,119 and 3,945,124; West German Pat. No. 2,440,692; West German patent application No. 1,804,253 and West German Utility Pat. Nos. 7 231 877 and 7 400 071, the disclosures of which are incorporated herein.
West German patent application No. 2,820,813 of Hans-Dieter Jacoby and Erich Schuster, published Nov. 15, 1979 and West German patent application 2,712,181 of Walter Werner, Klaus Herzog and Franz Szenger published Sept. 21, 1978 are incorporated herein to show sensing systems for sensing the test values at test samples.
Sensing systems for sensing the test values at test samples are known from West German patent application No. 2,712,181, wherein the movable parts consist of two pieces firmly joined together and between which are mounted one or more pickups sensitive to tension or compression, and wherein the connection between the housing fixed part and the movable part is implemented by an articulating member precisely determining the height of the movable part with respect to that fixed to the housing.
Further instrumentation for sensing the test values at test samples using a mechanical sensor moving with respect to the test samples and at least one test value transmitter is known, from West German patent application No. 2,820,813, wherein at the time of impact between sensor and test sample, a signal is generated for storing the test value at the time of impact at the test value transmitter in a memory and wherein the sensor consists of a housing fixed part and another integral part moving relative to the housing fixed part, at least one vibration or acceleration pickup being externally mounted on the movable part.
The instruments disclosed in West German Pat. applications Nos. 2,712,181 and 2,820,813 both suffer from the drawback that their high sensitivity makes them susceptible to spurious signals. To discriminate between spurious and sensing signals either a pulse identifying sensing must be generated additionally or a discriminator circuit, for choosing between the different oscillatory behaviors in sensor and spurious signals, must be provided. Both steps represent increased technical complexity with corresponding increased costs.